The following paragraphs are provided by way of background to the present disclosure. They are not however an admission that anything discussed therein is prior art or part of the knowledge of persons skilled in the art.
The reliable and rapid detection of chemical compounds in a liquid medium is desirable in many industrial processes, and detection methodologies uniquely relating a chemical property of a compound requiring detection to a detectable output signal are manifold. Recently, methods involving the use of reporter genes have been developed to detect the presence of chemical compounds. For example, the method disclosed in U.S. Pat. No. 6,391,549 permits the detection of a chemical compound using an electrochemical cell and a reporter polypeptide mediating the production of an electrically active compound. The method may be used to assay a single sample, or alternatively multiple samples may be assayed simultaneously. However the method is impractical where multiple chemical compounds require detection. In particular, in order to detect multiple chemical compounds, in accordance with the specification of U.S. Pat. No. 6,391,549, an electrical cell would be inserted in a first sample to detect a chemical compound, an assay result would be obtained, and then the electrical cell would be removed from the sample, cleaned and recalibrated for assaying for a second and any subsequent chemical compounds. Alternatively, two or more electrical cells are used in order to detect two or more chemical compounds. Thus, one of the drawbacks of the methods disclosed by U.S. Pat. No. 6,391,549, is that in order to detect the presence of multiple chemical compounds in an assay sample, it is required that either multiple assay samples are available, and, furthermore, that multiple electrochemical cells are employed, or that multiple non-simultaneous measurements are conducted. The former requires the presence of sufficient assay sample, and, moreover, requires a complex and impractical electrical component, in particular where a substantial number of different chemical compounds require detection. The latter is a time consuming methodology, and potentially more prone to operator error.
The reporter gene based methodologies for the detection of chemical compounds known to the prior art, including those provided by U.S. Pat. No. 6,391,549, are unsuitable for use in instances where it is desirable that multiple chemical compounds are detected in an assay sample. There exists therefore in the art a need for improved methods for the detection of chemical compounds.